Secretory-IgA antibodies play an important role in the immunity to Streptococcus pneumoniae

J Immunol. 2010 Aug 1;185(3):1755-62. doi: 10.4049/jimmunol.1000831. Epub 2010 Jun 28.

Abstract

This study was designed to investigate whether secretory-IgA (S-IgA) Abs induced by a pneumococcal surface protein A (PspA)-based nasal vaccine are necessary for prevention of streptococcal colonization. Mice nasally immunized with PspA plus a plasmid expressing Flt3 ligand (pFL) cDNA as a mucosal adjuvant showed significantly higher levels of PspA-specific S-IgA and IgG Ab responses in both plasma and nasal washes when compared with naive mice. Although IgA(-/-) mice given nasal PspA plus pFL had significantly high levels of PspA-specific IgG Abs, high numbers of CFUs were detected in nasal washes and nasal passages. In contrast, vaccinated wild-type mice showed essentially no bacteria in the nasal cavity. Further, a nasal vaccine consisting of PspA plus pFL effectively reduced pre-existing Streptococcus pneumoniae in the nasal cavity. These results show that PspA-based vaccine-induced specific S-IgA Abs play a necessary role in the regulation of S. pneumoniae colonization in the nasal cavity.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adjuvants, Immunologic / administration & dosage
  • Adjuvants, Immunologic / genetics
  • Administration, Intranasal
  • Animals
  • Antibodies, Bacterial / biosynthesis
  • Antibodies, Bacterial / physiology*
  • Bacterial Proteins / administration & dosage
  • Bacterial Proteins / genetics
  • Bacterial Proteins / immunology*
  • Bacterial Vaccines / administration & dosage
  • Bacterial Vaccines / genetics
  • Bacterial Vaccines / immunology
  • Cells, Cultured
  • Colony Count, Microbial
  • Female
  • Immunity, Innate* / genetics
  • Immunoglobulin A, Secretory / biosynthesis
  • Immunoglobulin A, Secretory / genetics
  • Immunoglobulin A, Secretory / physiology*
  • Membrane Proteins / administration & dosage
  • Membrane Proteins / biosynthesis
  • Membrane Proteins / genetics
  • Membrane Proteins / immunology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Streptococcal Infections / immunology
  • Streptococcal Infections / microbiology
  • Streptococcal Infections / prevention & control*

Substances

  • Adjuvants, Immunologic
  • Antibodies, Bacterial
  • Bacterial Proteins
  • Bacterial Vaccines
  • Immunoglobulin A, Secretory
  • Membrane Proteins
  • flt3 ligand protein
  • pneumococcal surface protein A